WHERE DOES THE ESCARGOT? TRACKING MARINE GASTROPOD LARVAE USING STATOLITH AND PROTOCONCH

Recent advances in the use of geochemical tracers in calcified structures to study larval dispersal trajectories have focussed on utilizing the hard parts of fishes. Invertebrate ecologists have paid less attention to analogous tools for reconstructing invertebrate larval history, despite the equally pressing need to understand dispersal trajectories of invertebrate larvae. Larval invertebrates possess mineralized structures, including statoliths, protoconchs, carapaces, and larval skeletons, that potentially record a natural tag of a larva's origin and dispersal history in their elemental composition. Here, I examine the utility of protoconchs and statoliths as markers of natal origin in the marine neogastropod, Kelletia kelletii. First, I present data from culturing experiments that show Ba incorporates into larval shell and statolith of Kelletia kelletii as a function of seawater temperature and seawater Ba/Ca concentration. Second, I demonstrate that larval hard parts formed at geographically separated sites show distinct elemental signals. Together, these data suggest larval statoliths and protoconchs could be powerful new tools for tracking dispersal pathways and identifying source populations.